It’s going to be a hot one! Highs will be in the middle and upper 90s! This will be challenging today’s current records…Boston->98F in 1999 and Worcester->93F in 1900. It will also be on the humid side as dewpoints hover in the 65-70F range. Heat Advisories will be in effect from 1pm-7pm for the majority of the viewing areas as well as an Air Quality Alert for the South Coast, Cape Cod, and the Islands from 11am-11pm.
A cold front will approach the area on Wednesday. Highs will remain high near 90F with the threat of showers and storms starting midday. These storms may reach strong to severe status as severe weather indices are showing CAPE values from 1500-2500 as well as LI values from approximately -3 to -5. This front will be slow to move south due to the upper level air flow.
Consequently, the newly updated model runs have me questioning just how fast this cold front will moves south of the area as well as where it will stall out. The 00z runs are all showing the front heading far enough south on Thursday to usher in more relief from the heat and humidity. However, with the front so close to the South Coast, the Cape, and the Islands, there could be a lingering shower early on Thursday and possibly enough instability for a storm or two during the afternoon.
Friday continues to look dry in terms of the GFSx and the EURO, but the latest NAM now shows the front pushing far enough north to produce a few showers and storms on Friday morning and afternoon. That being said, I will continue to follow the long-range models as opposed to the 06z NAM which is depicting a more pessimistic view. At the moment, I am going with partly cloudy skies, low humidity, and highs near 80F…cooler coast. We will be monitoring the position of this front.
This weekend is looking sunny with low humidity and highs more seasonable. Saturday will be mostly sunny with highs in the lower 80s…70s coast. Sunday will reach the middle 80s with a breezy south wind.